RE: [PATCH v2] sysinfo: include availram field in sysinfo struct
From: David Laight <hidden>
Date: 2022-01-07 22:22:27
Also in:
linux-mm, lkml
From: Pintu Kumar
Sent: 07 January 2022 18:08 The sysinfo member does not have any "available ram" field and the bufferram field is not much helpful either, to get a rough estimate of available ram needed for allocation. One needs to parse MemAvailable field separately from /proc/meminfo to get this info instead of directly getting if from sysinfo itself. Thus, this patch introduce a new field as availram in sysinfo so that all the info total/free/available can be retrieved from one place itself.
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quoted hunk ↗ jump to hunk
diff --git a/include/uapi/linux/sysinfo.h b/include/uapi/linux/sysinfo.h index 435d5c2..fe84c6a 100644 --- a/include/uapi/linux/sysinfo.h +++ b/include/uapi/linux/sysinfo.h@@ -19,7 +19,8 @@ struct sysinfo { __kernel_ulong_t totalhigh; /* Total high memory size */ __kernel_ulong_t freehigh; /* Available high memory size */ __u32 mem_unit; /* Memory unit size in bytes */ - char _f[20-2*sizeof(__kernel_ulong_t)-sizeof(__u32)]; /* Padding: libc5 uses this.. */
There are 4 pad bytes here on most 64bit architectures.
+ __kernel_ulong_t availram; /* Memory available for allocation */ + char _f[20-3*sizeof(__kernel_ulong_t)-sizeof(__u32)]; /* Padding: libc5 uses this.. */ };
You've not compile-time tested the size of the structure. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)